Why was Krishna actually not sleeping? Because He was thinking about Srimati
Radharani, thinking about the Vraja gopis. Before Krishna could
answer, they suddenly saw some injury on His feet. They asked,

"How did You hurt Your feet? Oh, is it because of this injury that You cannot
sleep? Tell the truth, tell the truth," they insisted.

Then, Krishna said, "Actually, My heart is cool because Radharani's lotus
feet are in My heart, and as for the other things, yes, My body is burning
because I have hurt my feet..."

"How will you sleep then? What can we do for You?"

"Well, you can give Me some milk..."

Then, they boiled some milk and gave it to Krishna. After Krishna drank the
milk, He fell sleep.

I have seen this very nice story in Garga-samhita.

Our conception is service of Vraja gopis and Radharani and Her
associates, but we are not qualified for that. Even Vraja gopis
themselves say, "We are not qualified," then we must think that we are not
qualified. What to speak of Vrindavan, gopis, and so on, this is the
highest place—we cannot even compare ourselves to Rukmini and Satyabhama. It
is very difficult. When Rukmini and Satyabhauma saw Srimati Radharani, they
actually surrendered to Her and the Vraja gopis. With this in mind we
are going to their place.

'My master, Prabhupad Srila Bhakti Siddhanta Saraswati Thakur, established the religion of the age, Krishna-sankirtan, and is the chief minister of the universal assembly of leading Vaisnavas. His lotus feet are worshipped by millions of virtuous souls and fulfil the desires of those who dispel souls' fears. Eternally I offer my obeisance to my master's worshippable feet.'